lily/misc.cc

   1 /*
   2   misc.cc -- implement various stuff
   3
   4   source file of the GNU LilyPond music typesetter
   5
   6   (c) 1997--2004 Han-Wen Nienhuys <hanwen@cs.uu.nl>
   7     Jan Nieuwenhuizen <janneke@gnu.org>
   8 */
   9
  10 #include <math.h>
  11 #include "misc.hh"
  12
  13 /*
  14   Return the 2-log, rounded down
  15  */
  16 int
  17 intlog2 (int d)
  18 {
  19   assert (d);
  20   int i=0;
  21   while ((d != 1))
  22     {
  23       d /= 2;
  24       i++;
  25     }
  26
  27   assert (! (d/2));
  28   return i;
  29 }
  30
  31 double
  32 log_2 (double x)
  33 {
  34   return log (x)  /log (2.0);
  35 }
  36